1. Field of the Invention
The present invention relates to an image forming apparatus and a method of forming images, and is advantageously applied to an image forming apparatus that uses color toners and a white toner to form images on a recording medium.
2. Description of the Related Art
A conventional printer receives image data from a computer and prints the received image data. The printer includes a plurality of image forming units, each unit being capable of forming an image of a corresponding color.
The printer includes four image forming units that form cyan, magenta, yellow, and black, respectively. The printer may also have an image forming unit that forms a white image in addition to the four image forming units. The white image forming unit prints a solid white image on an entire printable area of a recording medium before color images are printed. The white image forming unit is advantageous when underlayer printing is performed. Underlayer printing is advantageous when an image is printed on a non-white recording medium. A solid white image is first printed directly on the non-white recording medium, thereby covering the non-white recording medium. Color images are then layered one over the other on the solid white image.
The white image forming unit may also be used to print a white-only image with gradation levels on a non-white recording medium.
Image forming apparatus are expected to be capable of printing not only a multi-color image but also an image of a single color or a limited number of colors with good print quality.